Safety-catch for mining-cages.



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SAFETY CATCH FOR MINING GAGES. APPLICATION FILED NOV. 14, 1912.

1,080,648. Patented Dec.9,1913.

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COLIN METHVEN, OF HERMINIE, PENNSYLVANIA.

SAFETY-CATCH FOR MININCT'- CAGES.

Specification of Letters Patent.

Patented Dec. 9,1913.

Application filed November 14, 1912. Serial No. 731,300.

To all whom t may concern:

Be it known that I, COLIN METHVEN, a citizen of the United States,residing at I-Ierminie, in the county of Westmoreland and Sta-te ofPennsylvania, have invented new and useful Improvements in Safety-Gatches for Mining-Cages, of which the following is a specification.

My invention relates to safety appliances for hoists, and thoughprimarily designed for hoisting cages for mining shafts, it may be usedfor elevators of various kinds, inclined railways, and the like.

The object of my invention is to provide an automatic safety devicewhich will prevent the cage from dropping in case the hoisting cableshould pull out of its socket or break off between the cage and mysafety device.

Referring to the accompanying drawings, Figure 1 is an elevation of atwo deck mining cage with my improved automatic safety device appliedthereto. Fig. 2 is a central vertical section of that part of the safetydevice in which my invention resides. Fig. 3 is a section of Fig. 2 onthe line III--IIL Fig. 4t is a perspective View of one of the lowerwedge-blocks with fragments of the parts directly attached thereto.

On the drawings, l represents a mining cage having the two decks 2 and3. The cage is supported by the chains l having their lower ends securedto the cage and their upper ends to the ring 5.

6 represents the hoisting cable made of strands of steel wire twistedspirally in the usual manner. The lower end of the cable is anchored inthe socket 7 of well-known construction, the upper end of the cableleading to any approved hoisting apparatus. Ordinarily, the cable ispassed over a sheave and then to the cable-drum of a hoisting-machine.At a suitable distance above the socket 7 I provide the cable with apair of clamping members 8, one on each side of the cable. The members 8have the vertical grooves to receive the cable, the grooves having theirwalls spirally recessed to conform to the spiral twist of the cable, sothat the cable cannot slip through the clamping members when the latterare tightly clamped to the cable. The members 8 are drawn toward eachother so as to clamp the cable between them by the bolts 9. The outerside or face of each member 8 is provided with a wedgeshaped rib ortrack l0, which inclines downwardly and outwardly away from the cable,that is, the two members 8 have diametrically opposite ribs or tracksinclining downwardly and away from each other. rlhe ribs are mostlylocated between the bolts 9 on the opposite sides of the cable so thatthe wedge blocks 11 presently to be described will act to draw togetherthe members 8 lwhere the bolts 9 produce their clamping action. 'Ihewedgeblocks 11 extend out horizontally and have their inner or opposingfaces inclined to correspond to the inclination of the clamping members10. Preferably the ribs and wedge-blocks will have interlitting tonguesand grooves, it being immaterial which has the tongue or groove, but Ihave shown the clamping members with the grooves and the wedge blockswith the tongues. yThe tongue and groove arrangement serves as a guidefor the wedge-blocks and prevents them from twisting out of their lineof travel. The wedge-blocks are connected together by the tie-bars 1Q,which extend through the slots 13 in the clamping members S and are secured to opposite sides of the wedge-blocks 11 by the bolts 14. Theslots 13 extend vertically below the bars 19. when in their nori malposition at or near the top thereof, to permit the wedge-blocks totravel downwardly for a purpose to be described hereinafter.

To the lower ends of the members 8 I connect the upper ends of the lowerclamping members 15 by means of the pivots or bolts 1G. The members 15have horizontal slots 17 for the bolts 16 to permit them to movelaterally independently of the upper clamping members S. The slots andpivot bolts are so made that the members S can move freely toward thecable without being held back by the members l5. The lower ends of themembers 8 are recessed to receive the members l5, the recesses beinglarger than the adjacent ends of the members 15 so that the members Sand 15 can move laterally without hindrance .from each other. Theopposing faces of the members 15 are spirally grooved like the members Sto lit the spiral exterior' of the cable (i. The outer diametricalopposite faces of the members 15 are inclined downwardly and away fromeach other and the cable, like the ribs 10. 'lhe wedge-blocks 18,resembling the wedgeblocks 11, have their opposing faces correspondingto the inclination on the members 15. The blocks 18 are connectedtogether by the two tie-bars 19 by means of the bolts 20 and 21. Theupper and lower wedgeblocks 11 and 18 are connected together by thelinks 22, their lower ends being connected to the bolts 20. The linksmay be arranged in pairs on the outside of the blocks, if desired. Thebridle-chains 23 have their lower ends connected to the cage 1 and theirupper ends to the blocks 18, by means of the bolts 21. These chains hangloosely so that there is normally no strain on them.

It is readily seenthat, in case the chains 4 break, or the cable 6 pullsout of the socket 7, or the cable parts between thesocket and the safetyclamp or catch, the bridle-'chains 23 would be drawn downwardly by thecage,

causing the wedge-blocks 18 to wedge the lhoist cable', a pair ofcable-clamping members having vertical slots at each side of the cable,there being a wedge-shaped surface clamping members 15 tightly to thecable. The do-wnward movement of the wedgeblocks 18 would through thelinks 22 `and their lost motion connection with the upper wedge-blocksdraw the wedge-blocks 11 downwardly and cause the members 8 to grip thecable with greater force than they were being gripped by the action ofthe bolts 9.

By the united wedging action of both sets of wedge-blocks, I produce avery strong and reliable safety catch for hoist-cables, each set ofclamping members being unhindered by the other as would be the case ifthe members 15 were integral or rigid with the members 8.

I provide the clamping members with corresponding tongue and grooveconnections as shown in Fig. 3, where 24 represents the tongues fittingin corresponding grooves.

I claim- 1. In a safety device for hoist cables, a hoist cable, clampingmembers gripping the same, there being inclined ribs on the clampingmembers, a pair of cable-clamping me-mbers pivoted to the bottom of thefirst named clamping members and having their outer faces inclined, apair of wedge-blocks cooperating with the inclined ribs, a pair ofwedge-blocks coperating with the inclined faces of the lower clampingmembers, links connecting the upper and lower' pairs of wedge-blocks, aload attached to the cable, and bridle-chains connecting the load andthe lower wedge-blocks.

2. In a safety device for hoist cables, a hoist cable, clamping membersgripping the same, there being inclined ribs on the clamping members, apair of cable-clamping members pivoted to the bottom of the first namedclamping members and having their outer faces inclined, a pair ofwedge-blocks cooperating with the inclined ribs, a pair of wedge-blockscoperating with the inclined hoist cable, two pairs of cable grippingmembers having diametrically opposite wedging surfaces, pairs ofwedge-blocks adapted to coperate with the said wedgmg surfaces to causethe gripping members to grip the cable, means connecting the members ofeach pair of wedge-blocks,means-connecting the pairs o-f wedge-blocks, aload connected to the cable below the gripping members, andbridle-chains connecting the load and the gripping members.

4i. In a safety device for hoist cables, a

on each clamping member, wedge-blocks slidable on the said surfaces,tie-bars eX- ytending through the slots and co-nnected to thewedge-blocks, a lo-ad connected to the cable below the clamping members,and means connecting the load to the rwedgeblocks.

5. In a safety device for hoist cables, a hoist cable, a pair ofcable-clamping members having vertical slots at each side of the cable,there being a wedge-shaped surface on each clamping member,wedge-.blocks slidable on the said surfaces, tie-bars eX- tendingthrough the slots and connected to the wedge-blocks, a load connected tothe cable below the clamping members, and means connecting the load tothe wedgeblocks, the coperating faces of the wedgeblocks and theclamping members having tongue-and-groove connections.

6. In a safety device for hoist cables, a hoist cable, clamping membersgripping the same, a pair 0f cable clamping members yieldingly connectedto the first-named clamping members and having their outer facesinclined, a pair of wedge-blocks cooperating with the inclined faces ofthe second clamping members, a load attached to the cable below theclamping members, and bridle-chains connecting the load to thewedge-blocks.

7. In a safety device for hoist cables, a spirally twisted hoist cable,clamping members gripping the same, a pair of cable clamping membersloosely connected to the first-named clamping members and having theirouter faces inclined, a pair of wedgeblocks coperating with the inclinedfaces of the second clamping members, a load attached to the cable belowthe clamping members, and bridle-chains connecting the load to thewedge-blocks, the clamping members having spiral grooves fitting thespiral eX- terior on the cable.

8. In a safety device for hoist cables, a pair of upper clampingmembers, a pair of lower clamping members, a lost motion connectionbetween the two pairs of clamping members and means for causing each ofthe members to automatically grip the cable in case the cable shouldbreak between the 10 clamping members and the load attached to the lowerend of the cable.

Signed at Pittsburgh, Pa., this 4th day of November, A. D., 1912.

COLIN METHVEN. Witnesses:

F. N. BARBER, ANNA R. BEATTY.

Copies of this patent may be obtained for ve cents each, by addressingthe "Commissioner of Patents, Washington, D. C.

